Loader for pin elevator

ABSTRACT

An improved means for compacting staple fibers into firm engagement with the pins of a pin elevator includes a multiplicity of flexible curved strips mounted in a circumferentially offset manner on a rotatable member adjacent to and extending horizontally across the width of the upward moving reach of the pin elevator.

United States Patent 1191 Selby 1 Sept. 30, 1975 1 LOADER FOR PIN ELEVATOR 2.811341 10/1957 Bogaty 198/161 2,907 076 10/1959 Beam 198/161 {75] Inventor: Donald W. Selby, W11m1ngton. Del. 2,920,355 W960 Clark 198/167 73 Assignccz E L' Du Pont de Nemours and 3,067,855 12/1962 Lambert 198/161 1 Compa y, w g a Ayres, Sr. [22] Fikid: Sept. 26, 1973 FOREIGN PATENTS OR APPLICATIONS [21 Appl. No.: 400,908

[52} US. Cl 198/161; 198/178 [51] 13656 15/22 [58] Field of Search 198/161, 167, 178; 19/975, 105, 204

[56] References Cited UNITED STATES PATENTS 1 170,825 12/1875 Dewey 198/161 894,494 7/1908 Gcb 198/161 1876.819 9/1932 Wucst. 19/105 X 2.301.088 11/1942 Stuhl 198/167 2,676,361 4/1954 Senior et a1 19/204 586.144 9/1933 Germany 19/204 Primary E.\'un1iner-Richard A. Schacher Assistant Examiner-Richard K. Thomson 5 7 ABSTRACT An improved means for compacting staple fibers into firm engagement with the pins of a pin elevator includes a multiplicity of flexible curved strips mounted in a circumferentially offset manner on a rotatable member adjacent to and extending horizontally across the width of the upward movinglreach of the pin elevator.

3 Claims, 2 DrawingFigures US. Patent s 30,1975 3,908,818

FIG-2.

LOADER FOR PIN ELEVATOR BACKGROUND OF THE INVENTION f This invention is concerned with the feeding'of staple fibers and more particularly with improved means for the uniform loading of low-density, turgid pneumacel fibers onto the pins of a pin elevator.

Use of a pin elevator to feed staple fibers is well known. In operation, a seriesof horizontal slats, each bearing a multiplicity of upwardly angled, sharpened pins, on a continuous belt is driven. upwardly pasta feed stock of loose staple fibers urgedtoward the pins by a slow-moving horizontal belt. The pins carry a lightly tangled mass of fibers upwardly past a spiked stripper roll which removes those fibers which project more than a certain distance beyond the slats and recycle them to the feed stock. Thus, as the belt carrying the slats moves across the top rolla fairly uniform amount of fibers is delivered by the pins to adoffer roll which removes substantially all the fibers and directs them to the subsequent stage of processing.

The pin elevator is not considered to be a highly accurate metering device and subsequent textile operations are relied on to compensate for unevenness in both its distribution across the width of the elevator and its total delivery per small unit of time. The lack of cross-machine and along-the-length" uniformity in delivery is largely due to (1) practical inability to provide a feed stock of uniform structure (resulting in nonuniform pickup by the pins), (2) the tendency of the fiber to clump and for the clump to inhibit access of fibers to the pins just below the moving clump (leaving a sparse area of fiber pickup) and (3) nonuniform stripping, due at least in part to the nonuniform engagement of the fibers on the pins of the elevator as they approach the stripper roll.

The fundamental bases for nonuniform delivery are exaggerated in the handling of buoyant, turgid pneumacel fibers, which tend to spring away from any tenuous engagement with the pins. The special requirements for feeding pneumacel fibers are recognized in US. Pat. No. 3,717,904 and a compaction roll is provided thereby to make a more compact mat of the fibers on the pin elevator. While the compaction roll offers an advantage over the art, it is apparent that further improvement is necessary to the objective to deliver a uniform amount of pneumacel fiber with respect to both machineand cross-direction distribution and rate. A means to compensate for the sparse area of pickup immediately following a picked-up clump of fibers is still needed.

SUMMARY OF THE INVENTION from said member. The flexible curved strips are mounted in a circumferentially offset manner but substantially contiguously in the axial direction on the rotating member. The rotating member is driven in the direction to presentthe convex sides of said curved strips to the fibers tenuously held by the pins of said elevator so as to urge said fibers downwardly into firmer and more uniform engagement with said pins. I

RIEF DESCRIPTION OF THE DRAWIN FIG; '1- is-a schematic side elevation view of portion of a conventional pin-elevator feeder as modifiedby inclusion of one embodiment of the apparatus of this invention; and

FIG. 2 is a schematic front elevation view of themtatable" assembly of flexible curved strips as seen from 2-2 In FIG. 1-: 1

DETAILEDDESCRIPTIONOF THE ILLUSTRATED EMBODIMENT Referring to the drawing, feed apron 10Iurges staple fiber feed stock 12 from source not shown toward pin elevator 13, which includes an endless belt having an upward moving reach 130. The pins 14 on p'in elevator l'llengage the nearest fibers'andraise them past compression rotor 15, flexible strips"l6 of which urge the fibers into firmer, more uniform engagement with the pins. As the engaged light tangle of fibers is brought past stripper roll 17, those projecting more than a predetermined distance above the pins are removed and returned to the feed stock. The fibers carried over roll 18 by the belt are discharged by means not shown to the subsequent stage of processing.

In this embodiment, flexible strips 16 are made of stainless spring steel 0.03 1 inch thick and 3 inches wide and are curved in a convex surface 16a at their tip ends. They are assembled in alternating, -apart orientations into a hub or compression rotor 15 consisting of four angle members, adjacent strips being very close or in actual contact with each other, and the entire assembly being rigidly bolted together. The rotating member may be positioned up to 12 inches above the normal working level of the staple feed stock to be presented to the pins and at a distance from the upward moving reach of the elevator to provide a clearance of from Vs to 6 inches between the tips of the strips and the tips of the elevator pins. The rotating member 15 is driven by means not shown at about 50 rpm and in the direc tion to present the convex surfaces 16a to the fibers held by pins 14 on the elevator. Pin elevator 13 is driven at a rate of about 60 feet per minute.

Baffle 19 is an optional feature which has been found of value in this particular embodiment. It is a 30-inch high sheet of noncorrodable metal of a thickness to result in good rigidity when mounted across the entire width of the space above the fiber feed stock and about 6 inches away from the tips of the flexible strips. The baffle curves somewhat below rotor 15 toward the upward moving reach of belt 13 and serves to retain an excess of fiber in the vicinity of the rotating strips and to assure availability of fiber to be pressed into the sparse areas on the pin elevator. With this baffle in place, the flexible strips are seen to be substantially immersed in a bed of tumbling fiber.

It will be obvious that alternative arrangements of the strips around the hub, alternative dimensions of the strips and adjustments in relative speeds and spacings are within the spirit and scope of this invention if the arrangement arrived at is capable of repetitive urging of staple filaments into more uniform and firmer engagement with the pins of a pin elevator.

It has been observed that the rolling action imparted to fibers at the juncture of feed apron and the pinned slats of pin elevator 13 results in clumps. or rolls, of fibers which finally are picked up by a section of pins. As this clump is moved upward through the fiber feed stock, it temporarily impedes progress of additional feed stock toward the pins, leaving them empty or only sparsely loaded. The compression roll of US. Pat. No. 3,7l7,904 was effective in urging such clumps into firmer engagement but was not capable of adding fiber to the sparse areas below them. The apparatus of this invention, however, appears to effect a gentle rearrangement of fibers on the pins by urging loosely held outer fibers from the larger clumps downwardly and into firm engagement with any pins as yet incompletely filled.

What is claimed is:

1. In an elevator for staple fibers including an endless driven belt having an upward moving reach with pins attached thereto for moving said fibers upward from a source of fiber stock presented to the pins the improvement comprising: a driven rotating elongated member positioned adjacent said upward reach, said member extending substantially horizontally across the full width of the upward moving reach of said belt; and a plurality of flexible curved strips extending radially from said member. said strips have convex surfaces at their ends, said surfaces being presented to the fibers held by the pins on said upward reach; and a fixed baffle positioned adjacent said member, said member being between said upward moving reach and said baffie, said baffle curving below said member toward said upward moving reach for retaining staple fibers in the vicinity of said curved flexible strips.

2. The elevator of claim 1, said strips being mounted in a circumferentially offset manner and substantially contiguously in the axial direction along the member.

3. The elevator of claim 1, said member being positioned a distance of up to 12 inches above said source, said strips having curved outward ends, said ends being spaced from said upward reach a distance of from A;

inch to 6 inches. 

1. In an elevator for staple fibers including an endless driven belt having an upward moving reach with pins attached thereto for moving said fibers upward from a source of fiber stock presented to the pins the improvement comprising: a driven rotating elongated member positioned adjacent said upward reach, said member extending substantially horizontally across the full width of the upward moving reach of said belt; and a plurality of flexible curved strips extending radially from said member, said strips have convex surfaces at their ends, said surfaces being presented to the fibers held by the pins on said upward reach; and a fixed baffle positioned adjacent said member, said member being between said upward moving reach and said baffle, said baffle curving below said member toward said upward moving reach for retaining staple fibers in the vicinity of said curved flexible strips.
 2. The elevator of claim 1, said strips being mounted in a circumferentially offset manner and substantially contiguously in the axial direction along the member.
 3. The elevator of claim 1, said member being positioned a distance of up to 12 inches above said source, said strips having curved outward ends, said ends being spaced from said upward reach a distance of from 1/8 inch to 6 inches. 